Long term objectives of this laboratory are to identify nutritional factors which contribute to the high incidence of colon cancer in Western cultures. Experimentally it has been suggested that dietary fat may serve in a promotional capacity in some manner following colon tumor initiation in two stage carcinogenesis. Although the relationship of dietary lipids to pre-initiation and promotional events in tumorigenesis are well studied, there is little information regarding the nutritional consequences on tumor behavior following tumor promotion, i.e., upon tumor growth, its spread, and its propensity to metastasize. It is hypothesized that the quality and quantity of dietary fat and cholesterol may influence tumor latency time, growth, pulmonary colonization, propensity to metastasize, lipid composition (profile) and demise of its host. To test this, the following will be accomplished: ascertain the relationship of diets containing varying levels of polyunsaturated fat (safflower oil) and saturated fat (hydrogenated coconut oil) with and without cholesterol to the growth and development of a highly metastatic CT-26 and minimally metastatic CT-51 transplantable colon carcinomas in the BALB/c mouse. The relationship of dietary interventions will be compared with the tumor implanted in the flank or surgically implanted into the colon. Differences in metastatic behavior between tumors at each site will be explored. Attention will be directed towards dietary influences on tumor behavior and the lipid profile of both tumors at each site. In addition the relationship of each tumor to the lipid profile of the host bowel, liver, and serum cholesterol levels will be assessed. It is very likely that nutritional interventions may influence the growth and metastatic spread of colon tumors. It is anticipated that these studies should provide 1) answers regarding differences or similarities between the effects of lipid nutriture on colon tumor induction and promotion and tumor behavior post-promotion; 2) a better understanding between lipid nutrition and colon cancer; 3) insights into the relationship between dietary cholesterol, hypocholesterolemia and colon cancer; and 4) guidelines for exploring possibilities of nutritional interventions aimed at the management of patients with colon cancer following resection or in conjunction with radiation or chemotherapy.